Hougardy Evelyne, Haff Ronald P, Hogg Brian N
Invasive Species and Pollinator Health Research Unit, United States Department of Agriculture-Agricultural Research Services, Albany, CA 94710, USA.
Foodborne Toxin Detection and Prevention Research Unit, United States Department of Agriculture-Agricultural Research Services, Albany, CA 94710, USA.
Insects. 2024 Oct 4;15(10):767. doi: 10.3390/insects15100767.
Sentinel eggs used to monitor field parasitism of stink bug pests (Hemiptera: Pentatomidae) can only be deployed for a few days to avoid releasing the pest in the monitored area. Using sterile eggs removes the risk of accidental pest introduction and extends deployment time. Freezing the eggs before deployment is one common method of sterilizing sentinel eggs. However, some egg parasitoid species have low or no parasitism on frozen eggs. In this study, X-ray irradiation was used to sterilize sentinel eggs intended for monitoring parasitism by (Hymenoptera: Scelionidae), the most promising biological control candidate. In this case, freezing sentinel eggs is not recommended because has low levels of parasitism on frozen eggs. Doses as low as 10 Gy induced 100% sterility. Irradiated eggs successfully sustained the development of and (Hymenoptera: Encyrtidae), another egg parasitoid attacking , and parasitism levels were comparable to that of fresh eggs up to seven days old. In addition, showed no preference for fresh non-irradiated eggs over seven-day-old irradiated eggs. Our results indicate that X-ray irradiation is a suitable alternative to produce safe and reliable sentinel eggs to monitor the egg parasitism of and possibly other species.
用于监测蝽象害虫（半翅目：蝽科）田间寄生情况的哨兵卵，只能放置几天，以避免在监测区域释放害虫。使用无菌卵可消除意外引入害虫的风险，并延长放置时间。在放置前冷冻卵是对哨兵卵进行灭菌的一种常见方法。然而，一些卵寄生蜂种类在冷冻卵上的寄生率较低或没有寄生现象。在本研究中，使用X射线辐照对用于监测[某种寄生蜂名称]（膜翅目：缘腹细蜂科）寄生情况的哨兵卵进行灭菌，[某种寄生蜂名称]是最有前景的生物防治候选者。在这种情况下，不建议冷冻哨兵卵，因为[某种寄生蜂名称]在冷冻卵上的寄生率较低。低至10戈瑞的剂量可导致100%的不育。辐照后的卵成功维持了[某种寄生蜂名称]以及[另一种寄生蜂名称]（膜翅目：跳小蜂科）的发育，[另一种寄生蜂名称]是另一种攻击[害虫名称]的卵寄生蜂，其寄生水平与7日龄新鲜卵相当，直至7天。此外，[某种寄生蜂名称]对7日龄辐照卵和新鲜未辐照卵没有偏好。我们的结果表明，X射线辐照是生产安全可靠的哨兵卵以监测[害虫名称]及可能其他物种卵寄生情况的合适替代方法。
